can someone help me, i use minecraft wii u and i made a mob spawner, its wont spawn...ANYTHING....AT ALL, i dont know what to do, i made the roof higher, its 21 blocks high (far enough to spawn a bit away)....i literly dont know what to do, is there like a limit to something, or whaat
Those types of spawners are really tricky to get to work. Mobs do not move if the player is too far away, and that design relies on mobs wandering in order to work. If there is any spawnable space within range of your farm it will render it pretty much inoperable.
You want a flushing type or a piston pusher type farm. Flushing types are cheaper, but piston pusher types are faster. You also need to build it high in the sky (so the player can stand 130+ blocks above the ground) or in a perimeter (260+ block circle dug down to bedrock). This will remove any possible spawning spaces other than in your farm.
Obviously a perimeter is a huge job, so going high in the sky is a more attractive alternative. Just make sure the ground is 130 or more blocks below where you stand and build the farm under that.